Uisge Beatha: Water of Life or Watered Down? Multivariate Methods for Whisky Class Differentiation

Methods

Whisky Origin and Chemical Data
Sample_no Descriptor Distillery P S Cl K Ca Mn Fe Cu Zn Br Rb
1 Blend Baile Nicol Jarvie 0.152 1.100 0.173 7.860 1.450 0.032 0.027 0.186 0.015 0.002 0.006
2a Blend Bells 0.653 1.580 0.238 4.930 1.400 0.019 0.110 0.242 0.021 0.005 0.003
3a Blend Chivas 0.375 0.809 0.193 4.310 1.220 0.019 0.044 0.196 0.007 0.003 0.002
4a Blend Dewars 0.121 1.160 0.157 3.200 1.140 0.011 0.050 0.189 0.018 0.003 0.003
5a Blend Johnnie Walker 0.326 1.090 0.180 5.480 0.526 0.018 0.103 0.286 0.020 0.002 0.002
6a Blend The Famous Grouse 0.145 0.615 0.097 2.740 0.416 0.009 0.050 0.208 0.007 0.002 0.001
7a Blend Whyte and Mackay 0.067 0.576 0.151 2.360 0.745 0.012 0.047 0.159 0.019 0.003 0.002
8a Blend William Grant 0.239 0.748 0.147 2.840 0.976 0.010 0.021 0.137 0.020 0.003 0.002
9a Counterfeit Unknown 1 0.089 4.060 0.066 0.336 1.240 0.007 0.154 0.085 0.038 0.005 0.001
10a Counterfeit Unknown 2 0.088 14.700 0.072 1.230 1.400 0.006 0.025 0.052 0.018 0.004 0.001
11a Counterfeit Unknown 3 0.279 15.900 0.083 0.811 1.360 0.006 0.057 0.038 0.016 0.002 0.002
12a Counterfeit Unknown 4 0.320 22.100 0.596 2.320 1.780 0.008 0.019 0.038 0.015 0.068 0.001
13a Counterfeit Unknown 5 0.120 26.100 0.071 2.370 1.630 0.010 0.082 0.187 0.194 0.012 0.005
14a Grain Grain matured 0.034 2.230 0.252 6.440 1.040 0.013 0.115 0.174 0.019 0.004 0.006
15a Grain Grain unmatured 0.084 5.530 0.113 3.250 1.350 0.012 0.076 0.164 0.046 0.010 0.003
16 Highland Glengoyne 1.040 5.570 0.343 24.200 0.857 0.023 0.197 1.251 0.041 0.004 0.016
17 Highland Glenmorangie 0.126 0.796 0.245 6.950 0.859 0.035 0.025 0.523 0.011 0.003 0.006
18a Island Bowmore 0.914 6.670 0.316 21.100 0.868 0.037 0.148 0.548 0.032 0.007 0.018
19 Island Bruichladdie 1.630 5.480 0.697 36.500 4.130 0.038 0.288 0.587 0.066 0.034 0.039
20a Island Bunnahabhain 2.240 7.540 1.350 36.200 2.120 0.051 0.184 0.580 0.057 0.014 0.037
21 Island Talisker 0.034 4.850 0.362 5.670 0.607 0.018 0.070 0.277 0.033 0.003 0.006
22a Lowland Auchentoshan 0.169 1.460 0.417 11.700 0.681 0.042 0.128 1.320 0.037 0.006 0.012
23a Lowland Glenkinchie 0.108 2.450 0.176 7.760 0.738 0.031 0.106 0.434 0.022 0.002 0.007
24 Speyside Balvenie 0.695 3.850 0.120 20.300 0.765 0.031 0.121 0.380 0.035 0.005 0.024
25 Speyside Craigellachie 0.096 0.819 0.177 6.110 0.633 0.024 0.094 0.239 0.025 0.005 0.006
26 Speyside Dufftown 0.883 4.640 0.130 14.000 1.050 0.030 0.078 0.533 0.024 0.002 0.014
27 Speyside Glen Elgin 0.115 1.350 0.404 9.270 1.400 0.031 0.046 0.195 0.029 0.006 0.009
28 Speyside Glenburgie 2.000 7.910 0.185 37.700 1.650 0.053 0.134 0.198 0.043 0.008 0.026
29 Speyside Glennfiddich 0.317 2.720 0.344 12.400 0.660 0.029 0.132 0.519 0.193 0.004 0.013
30 Speyside Glenrothes 0.953 4.110 0.399 16.700 1.830 0.041 0.137 1.030 0.029 0.007 0.014
31 Speyside Knockando 0.051 1.030 0.191 5.140 0.605 0.017 0.094 0.432 0.020 0.008 0.005
32 Speyside Linkwood 0.276 1.050 0.207 6.220 1.010 0.020 0.064 0.769 0.019 0.004 0.006

Initial viewing:

Assesment Mahalanobis Distribution

Summary of Surprise Categories
Distance Category Count/HZ %/P-val
Bottom_50% 22.000 68.8
50-75% 2.000 6.2
75-90% 0.000 0
90-95% 1.000 3.1
95-99% 4.000 12.5
Top_1% 3.000 9.4
Henze-Zirkler Test 1.325 <0.001

Post log-transformation

Assesment Log-transformed Mahalanobis Distribution

Summary of Surprise Categories
Distance Category Count/HZ %/P-val
Bottom_50% 17.000 53.1
50-75% 7.000 21.9
75-90% 5.000 15.6
90-95% 2.000 6.2
95-99% 1.000 3.1
Top_1% 0.000 0
Henze-Zirkler Test 0.984 0.137

Structure examination

Hotelling's T² Test Results
Comparison T² Statistic P-value
Counterfeit vs Speyside 7,083.10 0.009
Blend vs Speyside 213.48 0.026
Counterfeit vs Blend 928,150.00 0.009
Island vs Speyside 171.63 0.581

Whiskies of:

Provenance

Counterfeits

Blends & Grains

Differentiation within the PCA Space

Results

Discussion